Apparatus for casting metals



Nov. 5, 1929. J. ZUBLIN APPARATUS FOR CASTING METALS Filed Oct. 1'0, 192'! JULIUS by ATTO KN EY Patented Nov. 5, 192

APPARATUS FOR Application filed October 10, 1927, Serial No.

The present invention relates to chill devicesfor the casting of metals, particularly of aluminum and metals and alloys similar thereto, in the form of plates, bars or the like.

To cast such articles use is frequently made of chills with a so-called gate in the wall thereof- This gate consists of a vpassage extending from the upper inner edge of the wall of the chill downwards to the base thereof.

The technical disadvantages of such gates provided in the wall of the chill are first, that after each pouring the metal which has solidified in the passage in the wall has to be removed therefrom, second, the gradient of solidification is high, and third, the temperature of the molten metal arriving at the sur- 7 face of the metal in the chill is not constant.

It has also been proposed to make the chill U-shaped, and to provide a vertically movable wall closing the open side. This disclosure overcame the aforementioned disadvantages but the relative movement of the metal and the covering in wall adversely affected the uniform quality of the casting, which disadvantage is more marked when such sensitive metals as aluminum are being dealt with. In addition metal exudes from between the chill and the moving wall even though accurately machined and firmly pressed together with the resultant undesirable increase in friction therebetween.

The object of the present invention is to remedy these defects. The idea on which this invention is based consists in so arranging the apparatus that the covering-in wall, in so far as it does cover in the opening of the chill in the particular case, is perfectly stationary with respect to the chill. This being so the packing surfaces will no longer be moved relatively to each other, there will be no prevention of the covering movement by molten metal oozing through between the packing surfaces and finally the covering-in 45 wall and the cast mass lying against it recas'rrne METALS 225,157, and in Switzerland October '13, 1926.

main stationary relatively to each other so that the disadvantages of the previously improved apparatus are completely avoided.

The present invention proposes to either construct the covering-in wall flexibly like a band, so that it is possible in each case to bring that part of the covering-in wall which is to cover the opening of the chill up to the marginal surfaces at the side of the opening of the chill, but to keep the remainder of the upper part bent away from the opening of the chill; or to build up the covering-in wall during each pouring from separate small strip members (flat small bars) to be brought in succession and connectedly over each other in front of the opening of the chill.

Such a construction however makes it more diiiicult to arrange the supply device (the hopper of the two previously known arrangements) in the covering-in wall.

The present invention entirely abandons making the covering-in wall act simnltaneously as a supplydevice and instead provides a separate supply device say a casting gutter.

This, however, is not in any way a retrograde step, but on the contrary a substantial improvement in as'much as -'by doing so a fundamentally different and far better method is rendered possible. Whereas in particular in the two previously known arrangements the inflow to the surface of the metal was always limited'to the point only where the wall hopper opens into the interior, the mouth of a separate casting gutter i. e. separated from the covering-in wall, can be made to extend through the still open part of the side opening of the chill and not only as close as may be desired to the surface of the metal but any point in space over it.

Furthermore the supply device separate from the covering-in wall has the advantage of making any transference of heat between them completely avoidable. In the previously known arrangements, since there was a close thermal contact between the incoming metal and the wall of the chill, the result was an injurious premature cooling down of the metal or an injurious increase in the temperature of the covering-in wall; or both.

Another advantage of the use of a separate supply device, in comparison with the process with the previously improved arrangement, is that it renders possible adjustment of the separate supply device laterally in the interior of the chill and as close over the surface of the metal in the chill as may be desired.

It has also been proposed to close the open side of the chill with a flexible piece of sheet metal backed up by a solid plate, but the excessive friction between the metal sheet and the plate makes this construction disadvantageous.

A special type of construction of an arrangement according to the present invention in which a strip flexible about horizontal but not vertical axes is shown in the accompanying drawing.

In said drawings Figure 1 is a side elevation ofthe apparatus. Figure 2 is a front elevation in which the supply device is not shown.

Figure 3 is a plan view on a larger scale in which the uppermost part is cut away and the supply device is likewise not shown.

Figure 1 shows in detail elements3, 18 and The arrangement hereinafter described is adapted to cast bars of rectangular cross section and of a length equal to the vertical depth of the space of the chill.

The chill consists of the three vertical side walls, 1, 2 and 3 and the bottom 4. At the fourth side there is 110 wall and at that side the chill is open over the whole of the-vertical depth of the interior thereof. The ends 5 and 6 of the side walls 1 and 3 which lie in the same vertical plane may be regarded as the marginal surfaces of the opening in the chill as the part 7 of their plane lying between them forms the open part of the chill.

The chill 1, 2,3, 4 is adapted to move up and down between the vertical standards 9 and 10 fixed to and supported on the base plate 8, and can be moved up and down by means of the hand wheel 11 carried on the vertical screw spindle 12, the screw thread of which passes through a female screw thread in the cross piece 13 connecting the standards 9 and 10 at the top.

The strip for covering-in the opening 7 in the chill is composed of narrow horizontal small bars 14: arranged long side to long-side and pivotally connected to each other. The pivotal connection between the bars forms chain-like structures on both sides of the row of bars. The ends of the strip are pivotally joined to form anendless strip which runs over a pair of rollenchain wheels 15 and 16 which are mounted vertically over each other in a frame 17. One flat side of the strip lies in the plane of the opening 7 in the chill. The distance between the axes of rotation of these pairs of chain wheels 15 and 16 may be somewhat greater than the height of the chill and can be adjusted. The pivot pins 18 are prolonged slightly outwards on both sides, at the bottom of the chill two tappet hooks 19 are provided, one on each side, which engage with a pair of extended pins 18 mentioned above in such a way that when the chill is moved vertically, it carries downwards with it the flat part of the strip lying in the plane of its opening. At the same time the chill is pressed, under the pressure of rollers 20 controlled by springs or by the action of its own weight (in which case it rests on a falling supporting device and descends obliquely in the direction of the strip) against the flat part of the strip bearing against it so as to provide a liquid tight contact between the marginal surfaces 5 and 6 of the opening and the surface of the strip.

At the beginning of the casting operation,

the chill is in its highest position, and the bottom 4; of the chill is at about the level of the axis of rotation of the upperpair of chain wheels 15. At this stage the opening 7 in the chill is either not covered in at all or only just above the plane of the bottom 4 to a height, let us say, equal to a part of the width of a bar 14. If now the chill be moved slowly downwards by means of the hand wheel 11, one bar 14 of the strip after the other will pass from the upper chain wheel 15 with its face next to the chill into'the plane of the opening 7 in the chill and cover it an amount equal to the width of the bar. The

depth of the casting space thus closed inthereby increases gradually until finally the opening 7 in the chill is covered in up to the top edge of the chill as shown in Figures 1 and 2.

of time, and the downward movement of the chill must be regulated in such a manner that the level of the molten metal in the chill rises at the same rate as the chill descends. The level of the upper edge of the particular bar 14 last arrived in the plane of the opening -of the chill is always at or a little above the level of the molten metal. If the operation be carried out in this manner the opening 7 in the chill will in each case be covered'from below only so much as is necessary to prevent the metal from running out of the casting space again and the mouth of the casting gutter 21 passing through the opening 7 in the chill can be kept from start to finish of the casting operation at the level of the sur- 13o face of the molten metal in the chill or at any desired height above it. If the casting gutter 21 be made of suitable length and movable in a horizontal direction the metal can be allowed to flow in'each particular case to any desired point of the surface of the molten metal in the chill. The narrower the bars 14 are, the nearer the mouth of the casting gutter 21 can be brought to the surface of the metal in the chill, for the height of the gutter is determined by the diameter of the chain wheels 15 which may be made much smaller in radius when narrower bars are used.

In many cases it may be of advantage to provide the chill with not only one but a number of openings, which can be covered on opposite sides thereof. In such case molten metal may be allowed to run through two or more casting gutters 21 into casting space of increasing depth. This method may be of advantage, when working with a more favourable volume of supply per unit of time, for example, by making the speed of filling greater through each casting gutter than is possible with one and the supply of heat can be more favourably distributed over the surface of the metal in the chill.

In general it is convenient, as in this mode of carrying out the invention, to produce the covering-in operation by moving the chill downwards, because if instead of this the chain wheels 15 and 16 with the endless band were to be moved upwards along the station ary chill the casting gutter 21 would also have to be moved upwards whereas its level is preferably kept unaltered There may nevertheless be cases where the supply device is better raised, rather than lowering the chill.

Finally it is also possible to produce the covering-m operation part1 by lowering the chill and partly by raising the whole unit consisting of the chain wheels and the band.

Whether in the constructions in which the chill descends the chill be driven and the band carried along thereby as is the case in the arrangement illustrated, or whether the band be driven by driving say one of the of chain wheels 15, 16 and the "chill carried along thereby, is immaterial per se and a matter of convenience in each individual case.

In the construction illustrated the axes of the pivot pins 18 lie in the covering-in plane. In order at the same time to make the bending movement of the bars 14 relatively to each other possible they are cut away obliquely backwards. The advantage of this arrangement is that the gaps between the bars 14 can be kept closed even when the strip bends before it reaches the plane of the opening in the wall of the chill so that the possibility of any jamming action which might impede the free bending in the plane of the opening is precluded.

The square portion 22 on the end of the shaft of one of the pairs of chain wheels serves when the chill is right down at the pairs 1 bottom to turn the band alone by means of a crank handle for such a distance that the extended pins 18 again pass into their original position. What I claim and desire to secure by Letters Patent of the United States is 1. Apparatus for casting metal, which comprises a chill having an opening in one side means for feeding molten metal to said chill, said means being independent of said closure member.

3. Apparatus for casting metal, which comprises a chill having an opening in one side thereof, a movable endless band formed of interconnected narrow strips for closing said opening, and a gutter for feeding molten metal to said chill through said opening.

.4. Apparatus for casting metal, which comgrises a frame, a chillmounted to move vertically thereon, said chill having an opening in one side thereof, a movable endless band formed of interconnected narrow strips for closing said openingga gutter for feeding molten metal to said chill through said opening, and means for moving said chill and band simultaneously.

5. Apparatus for casting metal, comprisvertically thereon, said chill having an opening in one side thereof, a movable endless band formed of interconnected narrow strips for closing said opening, said strips being interconnected along their longer edges, a gutter for feeding molten metal to said chill through said opening, means for moving said chill and band simultaneously, and rollers for guiding said chill during said movement.

6. Apparatus for casting metal, comprising a vertical frame, a chill mounted to mbve vertically thereon, said chill having an opening in one side thereof, a movable endless band formed of interconnected narrow strips for closing said opening, said strips being interconnected along their longer edges, means for moving said chill, means interconnecting said chill and said band whereby movement of the chill causes corresponding movement of said band, and rollers for guiding said chill during said movement.

7. Apparatus for casting metal, comprising a vertical frame, a chill mounted to move vertically thereon, said chill having an opening in one sidethereof, roller chain wheels mounted on saidframe, an endless band passing over said wheels, said band being formed of narrow strips interconnected along their longer edges, means for moving said chill '100 ing a vertical frame, a chill mounted to move 1 vertically alon closing the feed opening in said frame, means interconnecting said c movement of said chill causes corresponding movement of said band, and rollers for guiding said chill during said movement.

8. In apparatus of the kind described, an endless band formed of narrow strips interconnected along their, longer edges arranged to form a closure member the casting chill, said band being provided with pins adapted to engage hooks on the chill to avoid relative movement during casting between the strips in closing position and the chill.

JULIUS ZUBLIN;

ill and said band whereby for progressively 

